Last week, the FDA urged doctors to lower the starting dose of zolpidem, a popular prescription sleep aid, due to concerns that the drug can linger too long in the body. This causes daytime drowsiness that has led to car accidents. Sleep aids affected by the FDA’s announcement includes generic zolpidem and brand names Ambien, Ambien CR, Edluar, and Zolpimist.

The FDA lowered the starting dose for women from 10 milligrams (mg) to 5 mg; for men it is now 5 to 10 mg. The drug should be taken right before going to bed.

The dosage change highlights what doctors prescribing sleep drugs are already acutely aware of: Taking too much can give you a “hangover” of daytime drowsiness the next morning that could raise the risk of accidents or falls.

“This just reiterates that zolpidem is a potent sleeping pill and very effective at getting people to sleep, but that lower doses may be all that you need,” says Dr. John Winkelman, medical director of the Sleep Health Center of Brigham and Women’s Hospital and associate professor of psychiatry at Harvard Medical School.

Sedating effects

Sleepiness is great when you are lying cozily in your bed. It’s a hazard if you are walking, driving, or working. Because people respond to medications in their own ways, it’s safest to start taking a sleep drug on a weekend, says Dr. Winkelman. He also has his patients begin taking a dose lower than the maximum recommended starting dose. If they feel drowsy the next day, the dose can be reduced; if it didn’t work, the dose can be increased.

Doctors are especially cautious in prescribing sleep aids for people over 65 because of the potential for harmful falls. Although this topic is controversial, and it remains unclear how often sleep drugs themselves can be blamed for falls, the starting doses for older adults are lower. Some geriatricians are wary of prescribing sleep drugs at all.

The right tool

Like any drug, prescription sleep aids should be tailored to the nature of the problem. “Some medications can help you fall asleep but not stay asleep; others are better for staying but not falling asleep; some can do both,” Dr. Winkelman says.

Zolpidem and other drugs developed to help with sleep are known as hypnotics. They vary in their ability to help you nod off and keep you asleep through the night. Zolpidem (Ambien, Edluar, and Zolpimist), eszopiclone (Lunesta), and zaleplon (Sonata) all help you fall asleep faster, usually acting within 20 minutes or so.

Of these, only Ambien and Lunesta have been shown in clinical studies to lengthen total sleep time. Sonata wears off fastest. That means it can help you fall asleep but not necessarily stay asleep.

A low-dose version of zolpidem that goes by the brand name Intermezzo is intended for people who wake up during the night and want help getting back to sleep. The recommended dose is only 1.75 mg for women and 3.5 mg for men. Intermezzo should be taken only once per night, and only if there are more than four hours left before needing to get out of bed.

A variety of other drugs for are available to combat sleeplessness; many were not developed for that purpose. They include benzodiazepines like triazolam (Halcion), lorazepam (Ativan), and temazepam (Restoril). The antidepressant trazodone (Desyrel), at a low dose, is frequently used as a sleep aid. A new type of drug, rozerem (Ramelteon), acts on the brain circuits that regulate the body’s day-night rhythm.

Use as directed

Taking sleep drugs at the right time (at the beginning of your sleep period) and at the right dose, helps prevent what doctors call carryover—the drug is still in your system and acting on your brain even after you wake up. The FDA recommendation underscores the fact that all sleep aids—not just zolpidem—should be used at the lowest effective dose. “It is better to undershoot than overshoot,” Dr. Winkelman says.

But sleep drugs aren’t right or necessary for everyone. Changing sleep habits and behavior can be helpful for people with occasional or short-term insomnia. This includes adopting a regular sleep schedule, creating a comfortable sleeping environment, avoiding alcohol and caffeine close to bedtime, and other steps known as “sleep hygiene.” (See Dr. Winkelman’s 10 tips for a good night’s sleep.)

If you do need an over-the-counter or prescription sleep aid, take it as directed and at the lowest dose that helps you sleep in order to prevent daytime drowsiness.